Q: Can I add NRC values together? A: NRC values can not be added together. For example Johns Manville Coated Insul-SHIELD Black® fiber glass board products feature an NRC of 0.70 for a 1 inch thickness and an NRC of 1.00 for a 2 inch thickness.
A: NRC values can not be added together. For example Johns Manville Coated Insul-SHIELD Black® fiber glass board products feature an NRC of 0.70 for a 1 inch thickness and an NRC of 1.00 for a 2 inch thickness.
